Fluid pressure harake



March 21, 1933. T. H. THOMAS FLUID PRESSURE BRAKE Filed May 22, 1929 H k W W mm kwmw wk HY Wm. WTB mK $5 ATTORNEY @wientM EL "425 5) @1 3 PEHHSYTUVAHM; WEI; H. 15 4 Q1? TEQMAE 1H: THUFIAS DEWEED MIIGNGE IQ s znwm n.

eeinssesie seem ipznieeeien flied my 932,

This invention relates is finial pressure brakes and mere penticnlwiy to s waive mechanism for cenemliing the on s cw: in s ins-in.

in We usual fluic'i pressure brake equipment empieying e brake pipe, enxiiiery reservoir, lie cylinder and triple veive device,

? nnsiee pressure for charging the eumineseweii is suppiied through the beaks s a feed gnoeve around. the tripie sine nisisen when the brakes see being re S@i;&ndi when the brakes are being applieii, ei'e 's efien n siigiit be-ck flow 01L fluid under essnre from the auxiliary reserveir the brake nipe through said feed. groove. 18 thus aimless that a considerable emennt of fluid under psessm'e is transmittal tizmugh the brake pipe in applying and releasing the brakes, which tends so retard the operation e1 the 'zi'ipie Waive device.

@ne objec sof my inventien is so l'kiGVldG an improved veive meehenism, fer centroi- 1 mg siie brakes on s can, which the shave dii ieuiisv is ebvieted,

@i; e1 objects enl selventeezee eppee in following more detailed diescri gition in my o q a q eccempenying drawing, i-ne e View eerily SE4,

e pressure brake equipme t em- :ig inveniieno i W in di the equi e eenfieefi g waive ieviee ee 2 bmcket i e chemise": 2 a i these 8 meuned sewise epplieetien emerges-2y eppiieeiie 8,

i eeni'prises seivice eppiiee'iien inrseugh seineci esgnei. eeioien Waive device *3 eom= nee seeiiens iii, 18 i2 eween the seeeiei. 1?

3. 529. Qefiei 1%. 865,227.

end as cever piste 16 is & flex ble diaphragm 12 anti ineerpesed between the casing sections 1? and 18 is a, flexibie diaphmgm 13. At the eppesise side of easing section 18 a flexible diephregm is is interposed between said section and the casing section 19, and stiii another diaphragm is interposed between the see= tien 19 ans. she easing section 20, a cover piste 21 being ineuntai on the oppesifce side 01? the seeeien 20.. 1

lnizenpesedl between disphmgms 12 end 13 is a foiiewei' piste 22, the first mentioned diephmgm being clamped against said foiiewes piste by a shoulder 23 on a cap screw 24, which base centrally disposed screw-threaded pension 25 engaging said foilowen The foiiewer plate 22 has 22, screw-threadeci poi"- tien 25 extending isnfrengh the diephregm 13 I) es e0 permit relative mavens-exit hediephiegms clamped 5e @0 1 iewei" vi @495 22'end 29,

A esp sense having flange has a three-tied stem 3% ezeending n e i5 and engaging the ieiiewer 22 'siiereby securing the diepinrsg'm i5 e, se that the i 15 enemies iegeiihen i wish the casing see-ties extending npwerdiy in she chamber 3'? is e ing 82, the upper feee 0? which femns 22- a siie xeive 39 epei'eitiveiy nieunied een siieuidee on diaphragm seem en& the heed of iiephregm nm;

siide valve 39 is maintained pressed piunger ei-U, cents-linen an e in depemiing ing; &1 zn'ni'i 63mg: m the upwardly enienciing ing pennen said siie waive.

meets into s suitebie here in n Chambers 43 and 44 are formed between diaphragms 12 and 13, and 14 and 15 and are permanentl in communication with the atmosphere t rough passages and 46 re- 5 spectively.

The casing cover plate 16 is provided with a stop lug 48 adapted to be engaged by she head of the cap screw 24, so as to llfi'lil the deflection of the diaphragm 12 and 13 to the leit. The chamber 47 at the outer. face of diaphragm 12 contains a. spring 49, which en gages diaphragm 12, urging said diaphragm lo the right.

The casing cover plate 21 is provided with a stop lug 51 adopted to be engaged by she heed oi the cap screw 34, so as to limit the defieclion 01" diaphregins 14 and 15 to she right.

The emergency valve device 7 of the brake equipmen comprises a quic action portion and s velve'por'bion.

The quick action portion of the emergency valve device comprises o casing having chamber 151' containing 21 piston 52 an e, chamber 53 containing a main slide velve and an auxiliary slide valve adopted '50 e ooereted said oisbon. 1 L 5 7 ned she chamber 151 and sets 57 slidoblv ins screivbreaded the casing. Movement 7 to the right is limited by eneinen of e flange 59 on said ".viifib on'ber end of he vent valve portion of we er-1e; valve device comlorises a brass valve 38 contained in e chm; 1 ten 52 for operating said ven; velve. biston 62 has a chamber one nd e chamber 64 the oo'oosite side, s idsblv mounted in suit ble bore in i 65 of "he casing is eel/em 66 of said oisaon.

" vent valve 6Q has 9. seem 6? extending into o bore in seen 66 or :the piston 6 The vent valve @0 also less seem =32 she opposite side extending into a bore in casing, said bore containing o. spring 7% on said stem. and urging soid valve seal rib 'Zl. 'Gonteined in chamber 83 l ining member one side oi? the piston 62, is spring 72 for nieineeining said piston in engagement vent valve slam 6?.

The ch ck valve oorion 8 com rises casing divided iniso sections '25, 7d Z interposed between the sections 75 is a flexible dia-p'liregm 73 and inizerpose beeween the opposite side of session 76 and the section 77 is s flexible diaphragm Z4. A slide valve 7 8 is contained in a chamber 7% formed at one side of the diaphragm 74 and within the casing section 77 and is Bldfifilllfid to be operated by deflection of said diaphrsgms. Said diaphragm are separated by a spacer 65 8D to which diaphragm 7 3 is clamped by a, nut

81 having screw-threaded enga menu on a stem 82 of said spacer. Diap ragm 74 is secured to said spec/er by a nut 83 having screw-threaded engagement on another sf/em 84 of said spacer. The stem 84 has an extension 85 projecting downwardly and slid ably mounted in a suitable bore in a cap screw 86, which screw is adapted to close one end of the chamber 79. Slidsbly mounfied on obe stem extension 85 is a flanged sleeve-like member 87 and interposed between said memleer end the cap screw 8% is s spring 88. Mounted between the flange on member 8? end the nut 83 is the slide valve 78, which is maintained seated by e spring pressed plunger 89.

A chamber 90 is formed at the upner side of the diaphragm 73, and a chamber 91, formed intermediate the diaphragm 73 and 74., is in constsni communication with the atmosphere by way of s passage 92.

in operation, fluid under oressure is sup plied to the brake pipe 93 by the operation of e. brake valve device (not shown) in the usual Well known menner. Fluid "from the broke pipe 93 flows through passege to diaphragm chamber 47 of the service applicalion valve device '3, piston chamber 151 of the emergency valve de ice 7 end diaphragm c as her 90 of be cl.ecl-: valve device 8.

en the diaphragm chambers 3? and 50 one service application valve device 6 initially at atmospheric pressur I oressure fluid in chamber 47 deflects e dicd 15 to the right until *0 The nressure of Imber 151 rorces {be piston o 5E to their extreme inner position, in which said pis'zon engages the casing, and the pressure of fluid in diaphragm chamber 30 of M18 check valve device deflecis the dieohrsr ms 3 78 end '74 downwardly, thereby shifting the slide valve 78 downwardly "so 3. position in which a port 95 in said slide valve registers with a passage 96.

Fluid under ressure from a main reservoir 9, "which is charged with fluid under pressure in the usual manner, flows through pipe end passage 96 to the seal; of the service application slide valve 39, to the seat of the emergency slide valve 54 and to the sect of the slide valve '38 in the check valve device.

With the slide valve 78 of the check valve device 8 shifted downwardly. as hereinbefore described, fluid at main reservoir pressure ilovvs from passage 96 through port 95 in said slide valve to valve chamber 79 end from thence through passage and pipe 97 to the control reservoir 10, to the diaphragm chamber 50 of she service application valve device and to the seat of the emergency slide valve 54.

l l hen the pressure in diaphragm chamber 79 of the check valve device becomes equal neees to 43 1' slightly greater then the hvehe pipe pvessuve acting in diaphragm chamber 99, then the diephnugms 73 end '74 use deflected I upwardly, permitting spring 88 to shift slide valve 78 upwardly end lee passage 95, so as to prevent further dew oil fluid under pressure from the main reservoir to the control veservoii l9.

-"With the diephmgu'i chamber 50 of t .e service application vnlve device 6 charged with at substantially the same pressure es th t carried in the hicks pipe 93 end ectin diaphragm chemher 4?, the pressure the spning 49 maintains the sevvice epplice Lon valve device in the normal running position, as shown in the drawing.

As heieinheioi'e descriloed, pipe pre sure acting in chamber 151 of the emeigency valve device causes the piston 52 to shift the slide velves 5% end 55 to their extreme inner position, in which e port 99 in the main slide vs 54: Z'egistevs with passage 96 icons main reservoir 9, end port 99 is uncoveied hy the auxiliary slide valve 55. Fluid pres sure is thus permi ted to flow icons. "res-evvoiv into velve chamber 53 and from thence through a passage 199 to the quick action chamber 2., When the oi'essuie in the quick action chamber and valve chemise? 53 thus heccines slightly greater than the heel-vs pipe pressure acting in the piston chemise-r 151, he piston 52 is shifted to the left, causing ne auxiliary slide valve 55 to move relative o the main slide valve 54: and thereby lap port J9, so as to prevent further fiovv fluid under pressure to said chambers. After the port 99 thus lapped, the piston 52 continues to move to left, and es the volume of the valve chamber 53 increases, the pressure in said chamber correspondingly veducesend when the pressure in said chemise? hes thus been seduced to suhstentielly live-lie pigye pz'essure noting on the opposite side of the piston, further movement of the tcvveid toe left ceases, end the piston remains in on, as shown in the drawing.

-l the equipment thus fully charged, the hicks cylinder 9 is connected to the st niosphere through pipe and passage 101, diechemhei- 37ml the service application velve device, passage 102 which is uncovered by slide valve 39, e choke plug 103 and on atmospheric pnssege 194., i

ii it is dslYBd to edect a service appliestion the lorekes, the pressure of the fluid in the brake pipe 93 is gradually reduced in the usual manner; Since diephvegm chamher l? of the service application valve device is connected to the brake pipe, the pres sure therein is also reduced :1 c'oiiespondiug degree.

As hereinheiore described, the valve chumber 37 intermediate diaphragms l3 and 14, is normally at atmospheric pressure due to the atmospheric connection by way of passage 192, end the diephrsgm chamber 59 is cherged with fluid substantially equal to the hi'ehe pi pressure edective in the diephvegm e ember 53'. Thus, when the hrelxe pipe pressure in diaphragm chsmloev 4:7 is reduced below the pressure in diephi'egm chamber 59, the pressure in chamber 59 neton diephi egin i5 ceuses seid dieohcugm to opevete end deflect the other diepnvegins i2, i3 lei to tl e left, thereby shifting the slide velve to service position, in which pessege 192 is lapped end iessege 96 "from the main reservoir 9 is uncovered. Fluid unde pvessuve thus is permitted to llovv from said reservoir to diephregin chamber 3? through it choke plug 195 in passage 96, end from chamber 3? through passage and pipe 191 to hnslze cylinder 11, thereby applying the leeches,

The larslse cylinder pressure eilective in chemloei" 3"? o l the service epplicntion valve device sets on the left side of diaphragm i l end on the right side of diaphra m 13. The diaphragm id is levgei' in sires t on the diephregin 13, so that the difierence in opposing forces on said diephrsgms 13 and M tends to deflect all the dieplirsgms and shift the slide valve to the weight, "When the diilerence in pressure ectingon the diephregins 13 1% thus becomes suflicient to slightly overhelence the didei'ence between the piessure in diephiegm chamber 50 acting en diephregin 15 end the reduced brake pipe pres sure diaphragm chamber l7 acting on dinphi'egm 12, the diephrsgms ere deflected to the right, hei'eh causing the slide valve 39 to be shifted an lep the fluid pressure supply psssege 96, so es to prevent further flow oi fluid under pressure to the brake cylindei,

lit is obvious from the shove description of the opevetion of? the service spplicntion valve device in efiecting at service application of the brakes that the degree of brake cylinder pressure oteined depends upon the degree of hielse pipe reduction eh ected. (louse quently, the brake pipe pressure may he re duced in steps and the brake cylinder pressure will build up in proportional steps, thereby eii'ecting a graduated epplicetion of the loveless. 7

When the brake pipe pressure is greoluel ly reduced in effecting a service application of the brakes, such reduction being effective in piston chamber 151 of the emergency valve portion permits the pressure of fluid in the valve chamber 53 to shift the emergency piston 52 and auxiliary slide valve 55 to the left into engagement with the stop member 57, in this position, the brake pipe passage 94 is connected to passage 101 through ports 115 end 116 in the main slide valve 54 and cavity 114 in the auxiliary slide valve 55, thereby permitting fluid under pressure to flow from the brake pipe to the brake cylinder and effect a quick service reduction in brake pipe pressure in the usual well known manner. In this position of the auxiliary slide valve 55, a port 107 in the main slide valve 54 is uncovered, which port registers with the atmospheric passage 104 in the main slide valve seat. Fluid under pressure in the valve chamber 53 and quick action chamber 2 is thus permitted to flow to the atmosphere at a rate substantially equal to the rate of reduction in brake pipe pressure. \Vhen the pressure in valve chamber 53 is thus reduced to a degree slightly less than the reduced brake pipe pressure, then the piston 52 shifts the auxiliary slide valve 55 back to its normal position.

In order to release the brakes after a service application, the brake pipe 93 is recharged with fluid under pressure. When the brake pipe pressure is thus increased, causing a corresponding increase in pressure in diaphragm chamber 47 of the service application valve device, the pressure acting on the left side of diaphragm 12 plus the brake cylinder pressure acting on the left side oi diaphragm 14 overbalances the pressure acting on the right hand sides of diaphragms 13 and 15 and causes the diaphragms 12, 13, 14 and 15 to be deflected to the right, thereby shifting the slide valve 39 to the right and uncovering passage 102, through which fluid under pressure is vented from the brake cylinder 11 to the atmosphere by way of pipe and passage 101, valve chamber 37, passage 102, choke plug 103 and atmospheric passage 104, thereby releasing the brakes.

In releasing a service application of the brakes, the emergency valve portion is shifted to its extreme right hand position in which the valve chamber 53 and quick action chamber 2 are recharged in the same manner as in initially charging the equipment.

If it is desired to effect an emergency application of the brakes, the brake pipe pressure is suddenly reduced, thereby effecting a sudden reduction in pressure in the diaphragm chamber 47 of the service application valve device 6, permitting the pressure in the diaphragm chamber 50 to deflect the diaphragms 12, 13, 14 and 15 to the left, thereby shifting the slide valve 39 and permitting fluid under pressure to flow from the main reservoir 9 to the brake cylinder 11 in the same manner as when a service application of the brakes is effected.

The sudden reduction in brake pipe pressure reduces the pressure in the emergency piston chamber 151, thereby permitting the pressure in valve chamber 53 to shift the emergency piston 52 and slide valves 54 and 55 to the extreme left, compressing spring 56 and causing the piston 52 to seal against the gasket 109. The piston 52 and graduatin valve 55 do not stop in their service position, as when a service application of the brakes is effected, since the rate of reduction in piston chamber 151 is greatly in excess of the venting capacity of the port 107 in the main slide valve 54, and the necessary difierence in pressure to shift said piston and slide valves to emergency position is therefore maintained on the opposite sides of said piston.

As the emergency piston 52 moves to emergency posit on, the graduating valve 55 initially uncovers port 107 and a port 110 in the main slide valve, thereby permitting fiuid under pressure from the valve chamber 53 quick action chamber 2 to flow through port 107 and passage 104 to the 8.512103" phere, and through port-110 and passage 111 to the vent valve piston chamber 63 for a reason to be hereinafter explained. As the piston 52 continues to move toward emergency position, the main slide valve 54 is engaged by the Lange 112 at the end of piston stem 113, and is thereby also moved to the left to emergency position, in which port 107 is disconnected from the atmospheric passage 104and connected to passage 111, so that fluid under pressure continues to flow to the vent valve piston chamber 63.

Fluid under pressure thus supplied to vent valve piston chamber 63, shifts the piston 62 to the left, thereby unseating the brake pipe vent valve 60, which permits fluid under pressure to he suddenly vented from the brake pipe 93 to the atmosphere through passage 94, vent valve chamber 61, past vent valve 60 and from thence through the atmospheric chamber 68, so as to transmit serially the sudden emergency reduction in brake pipe pressure, in the usual manner.

In emergency position of the slide valve 54 the atmospheric passage 104 is lapped, so that the fluid under pressure in valve chamber 53 and quick action chamber 2 is only vented to the quick action piston chamber 63, from whence it flows to the atmosphere through a port 125 in the quick action piston 62 and an atmospheric passage 126. By

.thus venting fluid under pressure only through the port 125, the piston 62 maintains the vent valve 60 unseated for a period of time sufficient to completely vent the fluid under pressure from the brake ipe.

With the emergency piston 52 and slide valves 54 and 55 in emergency position, a cavity 114 in the graduating valve 55 connects port s 115 and 116 in the main slide valve 54. The port 116 registers with passage 96 from the main reservoir 9 and the port 115 registers with passage 101 from the brake cylinder 11. so that fluid under pressure is permitted to flow from the main reoervoir to the brake cylinder by way of said cavity 114. In emergency position of the emergency portion, the control reservoir 10 is also connected to the brake cylinder 11 I moves? 5 through ipe emi posse @Le if? iroi reservoir 19 is "thereby connected to the in the resin siirie veive es, s psssege $118 one goessege and pipe 3m,

It vriii be coteri "shes when era. emergency application of the brakes is eii'ecvefl, both the resin reservoir 9 end com-rel reservoir 19 are connected to 'ii'le brake cyiiorier, so that e high iareise cyiin-fler pressure is obtained,

vireo :1 service eeioiiceeion of the a &1 h I w is eriec'teci, cyiirrder pressure profgorsomi the brake pipe reflection,

H18 opereiion of e, e service ep- 1 cy eppiiceiion is much rvice eppiicemon, since iflflllfi 1S soppii d to she brake cyiion or both service device emergency 12o To.

her be noted that "he propagaseriei venting or fluid under 1% oreise 39110823 to the eemoscod, by permiiiigg iiuiri under me "W &0 the vent veive piston cine s es mam siide voive 1s moved,

,1 y o port 1111? in said slide vsive end 1 T iis is an advantage, in time Emergency pision stem flange 112 Q in siicie valve 54', shore vviii be before the resin siicie veive to obtain e greater ciiiiee sees in pressure on she opposite sides of the eroergeriey piston 52, as required. to move seici Thus, during ibis hesiise' bion, the f fi iifin chamber is portly W1 fluid erifier pressure, so that the r 11 slide valve is moved to emergescy posses *1 the veive be operseed at nce, Tiler is eneiiier sdveniege in su opiyi "c nil-tier pressure to the vent 'veive pie ember. es Withmlli? sifting-tile 4.1.459 veve from its normei position, as

- for ins-is if ihe rosin slide veive fails to move, still ii 1e broke pipe veer, valve 60 vviii opereie to suddeniy reduce the brake pipe pressure in order so propegsie the emergency 2&0.

es hereioiaeiore described.

r wrgeci with liuid oi e pressure greater size pressure carried in the broke pipe, them first pressure acting in dispizre ro chamber 50 of the service application veve device vviii cause the brakes to foe eppiieoi in e degree proporiionei so the emoune of over-- charge or the difierence in pressure in said reservoir end the broke pipe, This is ohvious since it is the sense es ii the brake pipe pressure were r duced an amount equei to the degree of overcharge,

in case the control reservoir 19 does he come overcharged, s nce in order to reduce the pressure in saici reservoir, an emergency eppiication of the brakes is efiecied in the same or manner as irereinbezfiore described. The combrake cylinder 131 through the emergency poriion 7 and the pressure in said reservoir rerinses by flow to the brake cylinder 11. The brsises rosy then be reiesseri end the control reservoir will then recharge to the pressure to be carried in the brake pipe.

vviii be noted that the broke pipe 93 is only a meciimn through "which fluid under pressure is supplied "to or vented from the ,inverriion heen described in ciel'seii, 11; as

not my intention to iii-nit ifss scope to that emcodirnerie or oeiierise their by i'iie of zthe ep oeeoied cieims,

Having ncvv describeri my inveniion, Wires 3 cieim as new end desire to secure Toy Letters Pei/ens, is 2 In e iiciri pressure brake, 3 combineizion e Toreire pipe, Yoreire cyimder, and e moire reservoir, or? 9, control reservoir, e veive mechanism soojecii so the opposing pressures the oioe emi said control reservoir "for sppiying iiciri under pressure from she main reservoir "co control reservoir smi for the pressure in ssici control reservoir constant except in emergency, end s veive rievice subjece to "the opposing pressures the 'orei-re pipe and said cootroi res ervoir for cootroiiing the supply of fluid under pressure eotiie broke cyiinfier,

111 e fluid pressure ioreke, the combine vice with e oz-sire pipe, iorske cyiinder, and e rosin reservoir, of e control reservoir, c veive mechanism subject so the opposing pressures of the broke pine and scid; conirol reservoir for suppiyirig fliiid under pressure from the reservoir to said controi reservoir, and e veive device sucjeci: co the opposing pressures of the brake sips end seici control reservoir and opersieriupon e reelection in brake pipe pressure for supplying fluid unrier pressure from the resin reservoir to the broke cylinder.

3, In e fluid pressure or-eke, the combios= vice wise s brake pipe and e rosin reservoir, of veive device comprising e movoiiie simimerrs subject so "vile opposing pressures of the brske pipe eri e chamber, valve means operated by seici obcemem upon err increase brake pipe pressure for suppiyi'ng iiuirl under pressure from she main reservoir so said chamber and upon en increase in pre sure is seiri chemioer for costing the suppiyalso f pressure from said chamber to the atmosphere.

4. In a fluidpressure brake, the combination with abrake pipe, of a valve device subject to brake pipe pressure and the pressure in a chamber for controlling the brakes on a train, a main reservoir, valve means governed by the pressure in said brake pipe and operative to supply fluid under pressure from said main reservoir to said chamber and another valve device operative upon a reduction in brake pipe pressure to vent fluid under pressure from said chamber In a fluid pressure brake, the combination a brake of vaive device subject to brake pipe pressure a .d the press"- s chamber for controlli :he branes on a train, a main reservoir, valve means governed by the pressure in said brake pipe and operative to supply fluid under pressure from said main reservoir to said chamber, a brake cylinder, and means operative upon a reduction in brake pipe pressure to vent fluid under pressure from said chamber to said brake cylinder;

6. In a fluid pressure brake, the combination with a brake pipe, a main reservoir and a quick action chamber adapted to be supplied with fluid under pressure from the main reservoir, of a valve device subject to the opposing pressures of said brake pipe and chamber and normally closing communication through which fluid under pressure is supplied from the main reservoir to said chamber and movable from its normal position upon an increase in brake pipe ressure for opening communication throug which fluid under pressure is supplied from the main reservoir to said cham er.

7. In a fluid pressure brake, the combination with a brake pipe, 9. main reservoir and a quick action chamber adapted to be en plied with fluid under main reservoir, of a va ve device subject to the opposing ressures of said brake pipe and chamber an normally closing communication through which fluid under pressure is supplied from the main reservoir to said chamber and movable from its normal position upon an increase in brake pipe pressure for opening communication throu which fluid under pressure is supplied om the main reservoir to said chamber and movable upon an increase in pressure in said chamber for closing ofl the supply of fluid under pressure from the main reservoir to said chamber.

8. In a fluid pressure brake, the combination with a brake pipe, a main reservoir and a quick action chamber adapted to be supplied with fluid under pressure from the main reservoir, of a valve device for con-' trolling the supply of fluid under pressure to said chamber, said valve device comprisin a main valve having a port through whic fluid under pressure is adapted to be supressure from t e my hand, this iifl 'zh day of May, 1229 

